ROCK CF Rivers

Half Marathon & 5K

Run for your health. Run for the fight. Run to Rock CF.

More Than a Race:

It’s a Movement.

MARCH 22, 2026 | GROSSE ILE, MICHIGAN

The Rock CF Rivers Half Marathon is our signature spring event—uniting runners, walkers, families, and fighters to push limits and fuel hope. Every step supports the mission of Rock CF: to improve the quality of life for those living with cystic fibrosis through fitness, advocacy, and action.

With stunning views of the Detroit River and a USATF-certified fast, flat half marathon course around Grosse Ile, this race is a favorite for first-timers and seasoned runners alike.

Your choice of Half Marathon, a 15K (new!) or a 5K. Signup today to join us for year 15!

WHY WE RUN.

Every mile you run supports Rock CF’s life-changing programs, from scholarships to mental wellness programs to running shoes for those living with CF.

When you register, you’ll have the option to set up a fundraising page. Every dollar makes a difference.

BECOME A FUNDRAISER

Run Wherever You Are.

Can’t join us in Michigan? You can still be part of the Rock CF community from wherever you live. Register for the virtual run and complete your distance during race week and celebrate with the same shirt, medal, and mission!

REGISTRATION IS NOW OPEN!

Rivers Half Marathon, 15K (new!) & 5K FAQs

General Information

Sunday, March 22, 2026. The Half Marathon & 15K start at 8:00 AM from Grosse Ile Middle School
5K run/walk starts at 8:15 from the Grosse Ile Naval Hangar.
The Half Marathon & 15K start at 8:00 AM from Grosse Ile Middle School
5K run/walk starts at 8:15 from the Grosse Ile Naval Hangar
We offer:
- Half Marathon
- 15K
- 5K Run/Walk
- Virtual Run/Walk
Yes, the half marathon will be capped at 800, 15K at 300, and the 5K at 500 people.
YES!
Yes! There will be a 3 hour and 30 minute time limit for the half marathon. This breaks down to a 16 minute per mile pace. If you wish to continue beyond the limit, you will be on your own with no support provided by the race.
All proceeds from the race go to fund the mission of the Rock CF Foundation (www.letsrockcf.org)

Registration

Yes! You can change distances through your RunSignUp profile or email us for assistance.
Yes, if space is available. Early registration is recommended to guarantee your shirt and medal.
This race is the largest fundraising and awareness event for the Rock CF Foundation. Refunds will not be given in any event. You agreed to this when you registered.

Packet Pickup

Advanced Pick Up
Wednesday March 18 & Thursday March 19 at Run Detroit (1948 Division St. Suite 105 Detroit, MI)
Time: 10:00am-6:30pm
March 21 Race Expo (Pick up for all races)
Grosse Ile Middle School Gym (23270 E River Rd Grosse Ile)
Time - 12:00pm - 6:00 p.m.
________________________________
Sunday March 22
Race Day Half Marathon & 15K ONLY
Grosse Ile Middle School Gym
Time- 6:00am until race time
Race Day 5K Pick Up
Grosse Ile Pilot House (9645 Groh Rd, Grosse Ile )
Time- 6:00am until race time
Yes! They just need your name and event info. No ID required.

Gear Check

YES! See below for details
Half Marathon - Drop & Pick Up Inside of the GI Middle School Gym
5K - Drop at car parked outside of Hangar. Look for feather banner! Pick up in Middle School Gym
15K-Drop in Middle School Gym. Pick up at tent near finish line.
Use the bag provided at packet pickup and attach the label with your bib number. Volunteers will organize bags for easy pickup after the race.

Parking & Logistics

Half Marathon & 15K- Parking Options
1) Township Shuttle Lots by Grosse Ile Airport (Use the address 9801 Intrepid & enter off of Meridian Rd.)
- Pre race shuttles to the Middle School begin at 6:00am and run up until race time
- Buses will drive Half Marathon & 15K runners to the Middle School for the Packet Pick Up & Start Line
- Bus loading is on Saratoga Ave
- Buses will drive Half Marathon & 5K runners back to the lots from the Middle School after the race
- The 15KFinish Line is at the airport, runners can be shuttled to the Middle School after you finish. Post race 15K shuttle pick up is here.
We strongly encourage runners to arrive to these lots early, especially if you need to pick up your packet. Please allow plenty of time to park, and wait for bus loading. Shuttle time from the lots to the Middle School is 8-10 minutes but it will take longer.
2) Grosse Ile HIGH School - Limited Parking
- This is walkable to Grosse Ile Middle School for Half Marathon & 15K Packet Pick Up, Gear Check & Start Line
3) Macomb Street (Walking distance to Middle School)
Select business on Macomb Street are allowing us to use their parking lots for race day parking
- Please only park in the lots that have a Rock CF Race Parking sign in front of it
- These lots are on Macomb between Parke Lane & E. River
5K- Parking Options
1) Township Shuttle Lots by Grosse Ile Airport (Use the address 9801 Intrepid & enter off of Meridian Rd.)
- Both 5K Packet Pick Up & the 5K Start Line are across Groh Rd.
- Do NOT ride a shuttle to the Middle School before the race
- Buses will drive you back to these lots after you finish
- 5K Participants who ride the shuttles before the race from the Middle School will be dropped here.
2) Grosse Ile HIGH School - Limited Parking- This is walkable to Grosse Ile Middle School but you will need to take a shuttle down to the 5K staging area
3) Macomb Street- Walking distance to Middle School (You will need to take a shuttle to the 5K staging area)
- Select business on Macomb Street are allowing us to use their parking lots for race day parking
- Please only park in the lots that have a Rock CF Race Parking sign in front of it
- These lots are on Macomb between Parke Lane & E. River
EARLY!
If you need to take a shuttle to your packet pick up and start line, please allow extra time.
Travel time on a good day between both staging areas is 10 minutes. It will be congested and there will be lines.
Yes!
Pre Race Shuttles between the Township Parking Lots‍/5K Start and the Middle School will begin at 6:00am
- Bus loading to the Half & 15K start/packet pick up is on Saratoga Ave
- Bus loading & unloading at the Middle School is here
- 5K Runners who ride pre race shuttles from the Middle School to the 5K start/packet pick up will be dropped here
15K runners can be shuttled to the Middle School after the finish if needed. Post race 15K shuttle pick up is here.
We strongly encourage runners to arrive to these lots early, especially if you need to pick up your packet. Please allow plenty of time to park, and wait for bus loading. Shuttle time between the two staging areas Middle is 8-10 minutes but it will take longer.
Grosse Ile is an island connected by two bridges. The north end bridge costs $3.50 each way. The south end bridge is Free. Please note that because of trains and possible bridge openings your travel time could be delayed. Please plan to arrive on the island early to make sure you have ample time to prepare.
The Holiday Inn Express in Woodhaven (15-20 min from Shuttle lots) and Grosse Ile Pilot House are great options!
Grosse Ile and surrounding area has many restaurants that will be ready for you!

Race Day Details

No. USATF rules/insurance does not cover strollers on the course, so they are not permitted.
Our course insurance does not cover animals, well, domestic animals. Give your pet a break for the day!
Our water stations are the best! GIHS teams and clubs run these energetic stations!
Mile 2.5- Water
Mile 4.3- Water & Lemon Lime Gatorade
Mile 6.3- Water, Lemon Lime Gatorade & GU (vanilla, chocolate, tri berry, strawberry banana)
Mile 8.4- Water & Lemon Lime Gatorade
Mile 9.5- Water, Lemon Lime Gatorade & GU (vanilla, chocolate, tri berry, strawberry banana)
Mile 11.65 (Mile 1.65 for 5K)- Water
YES, you can wear headphones. YES, you can wear headphones. I know we've built this thing together, but I'd skip the Starship.
Half Marathon: Top Female, Top Male, Top Nonbinary, Overall Masters Female & Male, 3 deep per age group
15K: Top Female, Top Male, Top Nonbinary, Overall Masters Female & Male, 3 deep per age group
5K: Top Female, Top Male, Top Nonbinary, Overall Masters Female & Male, 3 deep per age group
Awards for the Half & 5K will be posted and handed out inside of the GI Middle School gym under The Bolts Rock CF Racing tent. 15K Awards will be at the finish line at the GI Airport.
Age Groups: 10 & Under, 11-14, 15-19, 20-24, 25-29, 30-34, 35- 39, 40-44, 45-49, 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80
You also will have access to live results on your smartphone.
YES! We have awesome peeps leading the following groups:
1:40, 1:45, 1:50, 1:55, 2:00, 2:05, 2:15, 2:30
Post race bagels, bananas, famous homemade cookies and other treats will be available inside of the Middle School. Please allow our awesome volunteers to hand you your food.
There will be cookies & bagels for 15K at your finish line!
There will be port-a-johns located around mile 2, 6, 8 & 10. There will also be TONS port-a-johns in the GI Middle School Parking lot and at the Start Line of the 5K.

Spectators

Yes! Spectators are welcome and encouraged.
There are awesome spectator areas at the Middle School, and around the course. Please see the course map to avoid driving on course.

Virtual Race

Yes! Just email us and we’ll help you update your registration. Info@letsrockcf.org
Please register for the virtual run before March 9th. Anyone who registers after March 1st for the virtual run will receive their packet AFTER the race weekend. Thank you for understanding!